Growth Rates of Five Freshwater Algae in Well-Buffered Acidic Media

1984 ◽  
Vol 41 (8) ◽  
pp. 1240-1243 ◽  
Author(s):  
Robert W. Gensemer ◽  
Susan Soltau Kilham
Keyword(s):  
Growth Rates ◽  
Physiological Responses ◽  
Freshwater Algae ◽  
Acidic Media ◽  
Treatment Groups ◽  
Ph Values ◽  
Asterionella Formosa ◽  
The Media ◽  
Similar Growth ◽  
Stephanodiscus Hantzschii

Growth rates for five freshwater algae, Asterionella formosa, Stephanodiscus hantzschii, Scenedesmus sp., Cryptomonas ozolini, and Anabaena flos-aquae, in media ranging in pH from 5.0 to 7.5 using three zwitterionic buffers, MES, PIPES, and TES, were determined. These buffers supported similar growth rates when compared with each other in treatment groups of similar pH. For pH values below 6.0 no growth occurred or growth rates were significantly reduced in some treatment groups for all species except Cryptomonas. In some cases, these lowered growth rates were partially or completely restored by reducing trace metals in the media by one or two orders of magnitude. We suggest that these buffers could provide a useful technique for investigating the physiological responses of phytoplankton in lakes undergoing acidification.

scholarly journals Differential Effects of the Allelochemical Juglone on Growth of Harmful and Non-Target Freshwater Algae

2020 ◽  
Vol 10 (8) ◽  
pp. 2873 ◽  
Author(s):  
Myung-Hwan Park ◽  
Keonhee Kim ◽  
Soon-Jin Hwang
Keyword(s):  
Green Algae ◽  
Algal Species ◽  
Allelopathic Effect ◽  
Freshwater Algae ◽  
Nuisance Algae ◽  
Asterionella Formosa ◽  
Fragilaria Crotonensis ◽  
Synedra Acus ◽  
Stephanodiscus Hantzschii ◽  
Algicidal Effects

Allelopathy has been applied to control nuisance algae in aquatic systems, but the effects of allelochemicals on the broad spectrum of algae are not well understood. We investigate algicidal effects of the allelochemical juglone on the bloom-forming, harmful algae Microcystis aeruginosa and Stephanodiscus hantzschii, and on several non-target algal species including cyanobacteria (Anabaena flos–aquae, Oscillatoria curviceps, and Phormidium subfuscum), diatoms (Asterionella formosa, Fragilaria crotonensis, and Synedra acus), and green algae (Chlorella vulgaris, Scenedesmus ecornis, and Scenedesmus quadricauda), in laboratory and field enclosure bioassays. Under three treatment concentrations (0.01, 0.1, and 1 mg L−1) of juglone, Microcystis cell density is significantly reduced by 35–93%. Concentrations of 0.1 and 1 mg L−1 inhibits Stephanodiscus growth almost equally (66% and 75%, respectively). To contrast, juglone produces a stimulatory allelopathic effect on three green algae, and other tested diatoms showed hormesis. Overall, the cyanobacteria are more sensitive to juglone than the green algae and diatoms. These results indicate that the allelopathic effects of juglone on microalgae vary depending on their characteristic cellular morphology and anatomy.

Mn-Mo-O Catalysts for Methanol Oxidation. I. Preparation and Characterization of the Catalysts

1992 ◽  
Vol 57 (12) ◽  
pp. 2529-2538 ◽  
Author(s):  
Krasimir Ivanov ◽  
Penka Litcheva ◽  
Dimitar Klissurski
Keyword(s):  
Methanol Oxidation ◽  
Solution Concentration ◽  
Alkaline Media ◽  
Acidic Media ◽  
Chemical Methods ◽  
X Ray ◽  
Ph Values ◽  
Precipitate Composition

Mn-Mo-O catalysts with a different Mo/Mn ratio have been prepared by precipitation. The precipitate composition as a function of solution concentration and pH was studied by X-ray, IR, thermal and chemical methods. Formation of manganese molybdates with MnMoO4.1.5H2O, Mn3Mo3O12.2.5H2O, and Mn3Mo4O15.4H2O composition has been supposed. It is concluded that pure MnMoO4 may be obtained in both acid and alkaline media, the pH values depending on the concentration of the initial solutions. The maximum Mo/Mn ratio in the precipitates is 1.33. The formation of pure Mn3Mo4O15.4H2O is possible in weakly acidic media. This process is favoured by increasing the concentration of initial solutions.

GROWTH RATES AND FERMENTATION PATTERNS OF LACTIC ACID BACTERIA ASSOCIATED WITH THE SAUERKRAUT FERMENTATION1

1971 ◽  
Vol 34 (11) ◽  
pp. 521-525 ◽  
Author(s):  
J. R. Stamer ◽  
B. O. Stoyla ◽  
B. A. Dunckel
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Growth Rates ◽  
Leuconostoc Mesenteroides ◽  
Lactobacillus Brevis ◽  
Sensitive Species ◽  
Ph Values ◽  
Generation Times ◽  
Effects Of Ph ◽  
Early Phases

The effects of pH values and NaCl concentrations on the growth rates of five species of lactic acid bacteria commonly associated with the sauerkraut fermentation were determined in filter-sterilized cabbage juice. Growth rates of all cultures, with the exception of Pediococcus cerevisiae, were retarded by addition of salt, lower pH, or interaction of both pH and salt. Based upon lag and generation times, P. cerevisiae was the culture most tolerant to the pH and salt concentration employed, whereas Streptococcus faecalis was the most sensitive species. Of the heterofermentative cultures, Lactobacillus brevis was less subject to growth inhibition than Leuconostoc mesenteroides. Under conditions simulating those found during the initial phases of the sauerkraut fermentation (2.25% salt, pH 6.2), L. mesenteroides displayed the shortest lag and generation times of all cultures examined. This rapid growth rate coupled with a marked accelerated death rate may explain, in part, the reason this species is both the first to dominate and the first to die during the early phases of the sauerkraut fermentation. Although cabbage juice previously fermented by L. mesenteroides appears to inhibit growth of P. cerevisiae, it had no apparent inhibitory or stimulatory effects on the other cultures.

A STUDY OF RATES OF GROWTH OF YORKSHIRE, LACOMBE, LANDRACE, AND CROSSBRED PIGS FROM BIRTH TO 200 LB

1964 ◽  
Vol 44 (3) ◽  
pp. 315-319
Author(s):  
J. M. Bell
Keyword(s):  
Growth Rates ◽  
Early Life ◽  
Growth Curves ◽  
Rates Of Growth ◽  
Similar Growth ◽  
Crossbred Pigs

Growth records were obtained from 12 research establishments across Canada for pigs fed according to current (1960–63) recommendations of nutrition and management. Growth curves showing age in days and weight in pounds are presented for the various breeds and crossbreds, for between-station comparisons, for comparison of upper and lower quartiles in purebred pigs, and for comparison of growth rates of purebreds with that of Yorkshires of 20 to 25 years ago.Age at 200 lb averaged from 152 to 187 days, among 10 stations for the Yorkshire breed. Pigs of each of the pure breeds reached 200 lb about 3 weeks earlier than that indicated in previous studies. Crossbred pigs of each of four different crosses grew more rapidly than average Yorkshires, some reaching 200 lb in 140 days and having gains in excess of 2.3 lb/day during the finishing period. Yorkshire, Lacombe, and Landrace pigs had similar growth curves. The upper quartile averaged 1.8 and the lower 1.4 lb/day gain between 100 and 200 lb weights. Slow-maturing pigs tended to be below average throughout life but differences in maturity between stations seemed to reflect differing rates of gain in early life, since finishing period gains were similar in 8 of 10 stations.

scholarly journals Effect of mint (Mentha piperita L.) and caraway (Carum carvi L.) on the growth of some toxigenic aspergillus species and aflatoxin B1 production

2009 ◽  
pp. 131-139 ◽  
Author(s):  
Marija Skrinjar ◽  
Anamarija Mandic ◽  
Aleksandra Misan ◽  
Marijana Sakac ◽  
Ljubisa Saric ◽  
...  
Keyword(s):  
Aflatoxin B1 ◽  
Dry Weight ◽  
Inhibitory Effect ◽  
Aspergillus Species ◽  
Mentha Piperita ◽  
Ph Values ◽  
Carum Carvi ◽  
The Media ◽  
Total Dry Weight ◽  
Poor Concentration

An inhibitory effect of various concentrations (0.0, 0.5, 1.0, 1.5 and 2,0%) of mint (Mentha piperita L.) and caraway (Carvum carvi L.) on the growth of A. fumigatus, A. flavus and A. ochraceus was examined during 10 days of cultivation in YES medium at temperature of 25?C. Mint showed stronger inhibitory effect than caraway. Total dry weight (g/l) after 10 days of the growth of A. fumigatus in YES medium with 0.5% of mint decreased by about 95%, A. flavus by 97% and A. ochraceus by about 82%. Addition of higher concentrations of mint (1.0, 1.5 and 2.0%) reduced the growth of all tested species. It was poor and hardly visible. pH values of the media increased with the increase of mint concentrations. A. fumigatus showed the highest sensitivity towards caraway and A. flavus the lowest. Total dry weight (g/l) after 10 days of growth of A. fumigatus in medium with 0.5% of caraway decreased by about 72% in comparison to the control. In media with higher concentrations of caraway, its growth was found to be very poor. Concentration of 1.0% of caraway reduced A. flavus growth by 15% and of 1.5% by 92%, in regard to the control. In medium with 2.0% of caraway the growth of A. flavus was observed as poor and hardly visible. The growth of A. ochraceus in medium with 0.5% of caraway decreased by about 85% comparing with control and further decrease was noticed by the increase of concentrations. In medium with 1.5% of caraway a reduction of about 95% of growth was found and under 2.0% of caraway it was poor. pH of the media also increased with the increase of caraway concentrations. Applied concentrations of mint and caraway inhibited completely the production of AB1 by A. flavus.

Effects of Truttaedacnitis truttae (Nematoda: Cucullanidae) on growth and swimming of rainbow trout, Salmo gairdneri

1980 ◽  
Vol 58 (7) ◽  
pp. 1220-1226 ◽  
Author(s):  
L. R. Russell
Keyword(s):  
Rainbow Trout ◽  
Growth Rates ◽  
Growth Characteristics ◽  
Salmo Gairdneri ◽  
Food Conversion ◽  
Critical Swimming Speed ◽  
Nematode Parasites ◽  
Conversion Efficiencies ◽  
Similar Growth ◽  
Food Consumed

Growth and swimming abilities of fingerling and 1.5-year-old rainbow trout infected with the nematode parasite Truttaedacnitis truttae were examined. Control trout and trout infected in the laboratory with 5, 10, 20, 40, or 80 worms exhibited similar growth characteristics over a 10-week period within each of four experimental groups fed different rations of trout chow (1, 2, 3, or 4% of wet body weight fed per day). Decreasing growth rates showed some correlation with increasing numbers of nematode parasites. Differences between growth rates, amounts of food consumed, and food conversion efficiencies of infected and noninfected fish were not statistically significant. Critical swimming speed, fixed velocity, and burst velocity stamina tests revealed similar swimming abilities in both control and infected trout. Maximum swimming speeds attained and time to fatigue at cruising speeds were more closely related to fish size than to numbers of worms with which fish were infected. Importance to rainbow trout survival of large natural infections with T. truttae is discussed.

scholarly journals Temperature effects on growth rates and fatty acid content in freshwater algae and cyanobacteria

2018 ◽  
Vol 35 ◽  
pp. 500-507 ◽  
Author(s):  
Jakob O. Nalley ◽  
Daniel R. O'Donnell ◽  
Elena Litchman
Keyword(s):  
Fatty Acid ◽  
Growth Rates ◽  
Acid Content ◽  
Temperature Effects ◽  
Fatty Acid Content ◽  
Freshwater Algae

Cardiovascular Safety and Sclerostin Inhibition – a mini-review

2021 ◽  
Author(s):  
Bente Lomholt Langdahl ◽  
Lorenz Christian Hofbauer ◽  
John Colin Forfar
Keyword(s):  
Clinical Trials ◽  
Cardiovascular Risk ◽  
Postmenopausal Women ◽  
Cardiovascular Events ◽  
Harmful Effect ◽  
Careful Consideration ◽  
Cardiovascular Safety ◽  
Treatment Groups ◽  
The Media ◽  
Canonical Wnt

Abstract Sclerostin is primarily produced by the osteocytes, inhibits the canonical Wnt pathway and thereby the osteoblasts, and stimulates RANKL release by the osteocytes and thereby osteoclast recruitment. Inhibition of sclerostin therefore causes stimulation of bone formation and inhibition of resorption. In clinical trials romosozumab, an antibody against sclerostin, increases BMD and reduces the risk of fractures compared to placebo and alendronate. The cardiovascular safety of romosozumab was adjudicated in 2 large clinical osteoporosis trials in postmenopausal women. Compared with placebo, the incidence of cardiovascular events was similar in the two treatment groups. Compared to alendronate, the incidence of serious cardiovascular events was higher in women treated with romosozumab. The incidence of serious cardiovascular adverse events was low and posthoc analyses should therefore be interpreted with caution, however, the relative risk seemed unaffected by preexisting cardiovascular disease or risk factors. Sclerostin is expressed in the vasculature, predominantly in vascular smooth muscle cells in the media. However, preclinical and genetic studies have not demonstrated any increased cardiovascular risk with continuously low sclerostin levels or inhibition of sclerostin. Furthermore, no potential mechanisms for such an effect have been identified. In conclusion, while there is no preclinical or genetic evidence of a harmful effect of sclerostin inhibition on cardiovascular safety, the evidence from the large clinical trials in postmenopausal women is conflicting. Romosozumab should therefore be used for the treatment of postmenopausal women with osteoporosis at high risk of fracture after careful consideration of the cardiovascular risk and the balance between benefits and risks.

A Comparison of Growth-Rates in Dependent Juveniles of Planigale-Gilesi and Planigale-Tenuirostris (Marsupialia, Dasyuridae)

1987 ◽  
Vol 35 (2) ◽  
pp. 161 ◽  
Author(s):  
DG Read
Keyword(s):  
Community Structure ◽  
Linear Regression ◽  
Body Condition ◽  
Growth Rates ◽  
Developmental Stages ◽  
Early Weaning ◽  
Body Sizes ◽  
Eye Opening ◽  
Body Parameters ◽  
Similar Growth

Growth rates are compared from birth to early weaning in Planigale gilesi and P. tenuirostris, by means of linear regression of body parameters plotted against age. Pouch young of each species had similar growth rates; an equation is given for the aging of pouch young of P. gilesi. Juveniles of P. gilesi grew faster than those of P. tenuirostris; in both species there was a trend for males to grow faster than females. Eye opening and the end of weaning were two important developmental stages, associated with changes to reduced growth rates. Changes in body condition of the juveniles indicated that the weaning process was initiated by the mother. The different growth rates between the species and sexes produced a range of body sizes in juveniles at independence. This has important implications for partitioning of food and for community structure.

An analysis of growth of different cattle genotypes reared in different environments

1984 ◽  
Vol 103 (1) ◽  
pp. 137-153 ◽  
Author(s):  
J. E. Frisch ◽  
T. E. Vercoe
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
High Growth ◽  
Environmental Stresses ◽  
Growth Potential ◽  
Gastrointestinal Helminths ◽  
Treatment Groups ◽  
Survival And Growth ◽  
Different Levels ◽  
High Growth Potential

SummaryCalves from three breeds, Brahman, Hereford × Shorthorn (HS) and Brahman × HS (BX), were divided equally into two groups, one of which was treated every 3 weeks from birth onwards to control ticks and gastrointestinal helminths, and one of which was untreated. Mortalities, growth rates and levels of resistance to environmental stresses that affected both mortality and growth under grazing conditions were recorded for all animals up to weaning (6 months) and for all males up to 15 months of age. The Brahmans were the most and the HS were the least resistant to environmental stresses, each of which was shown to depress growth in proportion to its magnitude and to contribute to the high mortalities of the HS. All breeds responded positively to parasite control with the greatest response in both survival and growth in the HS breed and the least response in the Brahman breed.Samples of males from the various breed-treatment groups were taken into pens where they were protected from environmental stresses and fed both low-quality pasture hay and high-quality lucerne hay ad libitum. Measurements were made of fasting metabolism, maintenance requirement, voluntary food intake and gain, variables related to the growth potential of each animal. The HS animals had the highest whilst the Brahmans had the lowest values for each variable.However, despite their low growth potential, the Brahmans had the highest growtli rate, and the HS, despite their high growth potential, had the lowest growth rate, when growth was measured in the presence of all environmental stresses. When parasites were controlled, growth rates were highest for the BX, the breed with intermediate growtli potential, and did not differ between the HS and Brahmans. These interactions arose because of the different contributions of resistance to environmental stresses and growth potential to growth rate measured at the different levels of environmental stresses. The relevance of these interactions to breed evaluation and cross-breeding is considered.Growth potential and resistance to environmental stresses were negatively correlated both between and within breeds, though the latter was biased by the effects of compensation. The influence of these relationships on the likely outcome of selection for increased growth rate, both between and within breeds, is discussed.

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